1. Field of the Invention
The present invention relates to air conditioning systems, and more particularly, to an air conditioning system having functions of cooling/heating, ventilation, and dehumidification.
2. Background of the Related Art
In general, the air conditioner cools or heats a room, such as a residential space, and office, to provide a comfortable environment. FIG. 1 illustrates a diagram a cooling/heating system of a related art air conditioner.
Referring to FIG. 1, the cooling/heating system of a related art air conditioner is provided with a compressor 1, a four way valve 2, an outdoor heat exchanger 3, an indoor heat exchanger 4, and an expansion device 5. There are an outdoor fan 3a adjacent to the outdoor heat exchanger 3, and an indoor fan 4a adjacent to the indoor heat exchanger 4. The cooling/heating system changes a flow direction of refrigerant flowing through the indoor and outdoor heat exchangers by switching the four way valve 2 under the control of a controlling part, for carrying out cooling or heating selectively.
A case when the cooling/heating system cools a room will be described. High temperature and high pressure refrigerant flows from the compressor 1 to the outdoor heat exchanger 3 as the four way valve is switched thereto, heat exchanges with external air, is condensed at the outdoor heat exchanger 3, and flows to the expansion device 5. Low temperature and low pressure refrigerant from the expansion device is introduced into, heat exchanges with room air, to absorb latent heat and vaporize, at the indoor heat exchanger 4, and flows to the compressor 1 again. In this instance, as the indoor fan 4a is rotated, the room air passes through, and cooled down at the indoor heat exchanger 4, and discharged to the room again, to cool the room to a constant temperature.
Next, case when the cooling/heating system heats a room will be described. The high temperature and high pressure refrigerant flows from the compressor 1 to, discharges latent heat, and is condensed at, the indoor heat exchanger 4. As the indoor fan 4a rotates, the room air passes through, and is heated at the indoor heat exchanger 4, and is discharged to the room again, to heat the room to a constant temperature. Thereafter, the refrigerant condensed at the indoor heat exchanger 4 passes through, expands at the expansion device 5, vaporizes to heat exchange with the external air at the outdoor heat exchanger 3, and introduced into the compressor 1 again.
The cooling/heating system cools or heats the room at a constant temperature as the foregoing process progresses repeatedly as cycles.
However, the cooling/heating system, cooling or heating the room air and circulating through the room repeatedly, contaminates room air and can not control humidity. When the room air is contaminated, and the humidity is not controlled, users feel unpleasant, and open a window for ventilation. Moreover, the discharge of room air to an exterior in the ventilation causes a large amount of energy loss, to require a large power consumption for cooling or heating required for brining the room temperature to a preset room temperature.